Environmental DNA (eDNA) metabarcoding of marine sediments has revealed large amounts of sequences assigned to planktonic taxa. How this planktonic eDNA is delivered on the seafloor and preserved in the sediment is not well understood. We address these questions by comparing metabarcoding and microfossil foraminifera assemblages in sediment cores taken off Newfoundland across a strong ecological gradient. We detected planktonic foraminifera eDNA down to 30 cm and observed that the planktonic/benthic amplicon ratio changed with depth. The relative proportion of planktonic foraminiferal amplicons remained low from the surface down to 10 cm, likely due to the presence of DNA from living benthic foraminifera. Below 10 cm, the relative proportion of planktonic foraminifera amplicons rocketed, likely reflecting the higher proportion of planktonic eDNA in the DNA burial flux. In addition, the microfossil and metabarcoding assemblages showed a congruent pattern indicating that planktonic foraminifera eDNA is deposited without substantial lateral advection and preserves regional biogeographical patterns, indicating deposition by a similar mechanism as the foraminiferal shells. Our study shows that the planktonic eDNA preserved in marine sediments has the potential to record climatic and biotic changes in the pelagic community with the same spatial and temporal resolution as microfossils.

海洋沉积物的环境DNA（eDNA）元条形码揭示了分配给浮游生物群的大量序列。这种浮游eDNA如何在海底上传递并保存在沉积物中的方式尚不清楚。我们通过比较在强生态梯度下从纽芬兰（Newfoundland）起飞的沉积物核中的metabarcoding和微化石有孔虫组合来解决这些问题。我们检测到低至30 cm的浮游有孔虫eDNA，并观察到浮游/底栖扩增子比率随深度而变化。从表面到10 cm，浮游有孔虫扩增子的相对比例仍然很低，这可能是由于活底栖有孔虫DNA的存在所致。在10厘米以下，浮游有孔虫扩增子的相对比例迅速增加，可能反映出浮游性eDNA在DNA埋藏通量中所占的比例更高。此外，微化石和超条形码组合显示出一致的模式，表明浮游有孔虫eDNA的沉积没有明显的侧向平流，并保留了区域生物地理模式，表明沉积的方式与有孔虫的壳相似。我们的研究表明，保存在海洋沉积物中的浮游eDNA可能以与微化石相同的时空分辨率记录中上层群落的气候和生物变化。表明沉积是通过与有孔虫壳相似的机制。我们的研究表明，保存在海洋沉积物中的浮游eDNA可能以与微化石相同的时空分辨率记录中上层群落的气候和生物变化。表明沉积是通过与有孔虫壳相似的机制。我们的研究表明，保存在海洋沉积物中的浮游eDNA可能以与微化石相同的时空分辨率记录中上层群落的气候和生物变化。